The most in-depth and practical analysis to date of the “3·21” explosion accident in Xiangshui (3)

Safety measures for accident prevention typically encompass intrinsic safety, engineering controls, administrative controls, and personal protective equipment. The implementation of intrinsic safety strategies and the adoption of engineering controls are primarily carried out during the research, development, and design phases. Consequently, to a significant extent, the design determines the inherent safety characteristics of a process unit.

Domestic engineering firms (design entities) generally maintain a high level of rigor in adhering to design codes and standards. However, referencing applicable codes and standards is merely the baseline for design; there is still room for improvement. For example:

1. Proactively pursue inherently safe design. Collaborate closely with the company’s R&D and process engineering departments to enhance the safety of process units by adopting an inherently safe design approach, for example, in areas such as plant layout, storage limits for hazardous materials, material handling, design specifications for critical equipment (including material selection), choice of heating media, and fault‑tolerant operating procedures, striving to implement solutions that maximize safety.

    

2. Collaborate with safety consulting firms or risk assessment organizations to refine the design scheme based on the findings of the risk assessment. For example, when developing the layout of process units, in addition to adhering to relevant standards and codes, you can also draw upon the quantitative simulation results provided by the consulting firm regarding the consequences of severe accidents to optimize the layout—particularly by prioritizing measures to mitigate risks in areas with high personnel density, such as the central control room and administrative office buildings.

3. Process hazard analysis is a critical step in enhancing design safety, yet many still fail to fully appreciate its importance. During the design phase, the engineering team should place greater emphasis on chemical process hazard analysis—including hazard and operability studies, or HAZOP—and actively participate in and support HAZOP reviews, ensuring that sufficient time is allocated in the project schedule to carry out this work.

   Note: At present, there are relatively few organizations in the market that offer high‑quality process hazard analysis services, such as HAZOP studies and SIL rating. Some engineering firms have also entered this field. If an engineering firm undertakes such work, it must establish appropriate mechanisms to address potential conflicts of interest; otherwise, if the person leading the process hazard analysis and the designers are colleagues—often even from the same department—they may “go easy” on identifying certain potential accident scenarios, thereby creating hidden safety risks. In foreign‑invested enterprises in China, it is typically the company itself (or a third party commissioned by the company) that leads the process hazard analysis, with the engineering firm participating and providing support.

4. Enhance the capability to apply critical safety technologies. At present, many small and medium-sized engineering firms (design institutes) in China still exhibit relatively weak competencies in the implementation of certain key safety technologies. For example, in the past, due to a lack of reaction‑heat data, many safety relief‑valve systems were sized based on experience or vendor‑provided specifications, without detailed release‑quantity calculations. Following the 2017 national mandate to conduct reaction‑heat measurements and risk analyses for fine chemical processes, numerous hazardous reactions now have documented reaction‑heat data, enabling engineering firms to leverage this information to design relief‑system configurations, including the calculation of emergency relief capacities. Consequently, it is essential to develop corresponding computational capabilities—particularly for two‑phase flow scenarios in relief‑system design. Moreover, in areas such as safety instrumented systems, explosion‑proof zoning (which should go beyond merely following the GB 50058 guidelines), and dust‑explosion prevention, many of our design organizations need to strengthen their technical expertise.

5. Among third-party stakeholders, equipment manufacturers play a crucial role—though we will set them aside for now. Chemical‑process equipment has a profound impact on safety across the chemical industry. Unfortunately, many manufacturers still hold outdated safety philosophies, focusing primarily on achieving process objectives while paying insufficient attention to safety considerations. For example, it is common to see rotating machinery with protective guards covering only half of the moving parts; likewise, numerous dryers and dust collectors used for combustible powders often lack essential explosion‑safety features, such as pressure‑relief panels. A decade ago, obsolete centrifuges were ubiquitous, leading to frequent accidents. In recent years, manufacturers have adopted nitrogen‑inerting systems and enclosed, automated operations—some even retrofitting existing units themselves—which have significantly reduced the incidence of accidents. Design firms serve as the bridge between end‑users and equipment manufacturers. If these firms incorporate more comprehensive and clearly articulated safety requirements into equipment specifications, they can not only help mitigate safety risks in ongoing projects but also encourage manufacturers to learn and improve. As a result, equipment safety is enhanced, and the entire industry’s safety awareness and overall performance are elevated.

6. Promote the refinement of regulations and technical standards. Some design firms have chaired or participated in the development of national safety‑related codes and technical standards, with their contributions widely recognized. Design firms can also establish more effective feedback mechanisms, encouraging engineers to report issues encountered in applying these codes and standards, consolidating such concerns, and providing timely responses—actions that greatly facilitate the improvement of relevant safety regulations and standards. Of course, national regulatory authorities and standard‑setting bodies should likewise put in place convenient channels for receiving and addressing feedback.

The deliverables of engineering firms (design entities) constitute a critical material foundation for ensuring the safety of process units. While we have many high‑caliber engineering companies, there remains considerable room for improvement in safety‑oriented design concepts and methodologies.

At present, all safety‑assessment entities are undergoing transformation, and the success of this transition will have far‑reaching implications for overall safety in the chemical industry. If the transformation is successful, a large number of specialized safety‑consulting firms will emerge, which would be a boon for chemical enterprises.

The safety assessment organizations bring together many highly qualified experts. In the past, when we were busy producing standardized safety assessment reports, many of these experts were unable to fully leverage their professional strengths. The current move to promote socialized services represents an excellent effort to unlock their full potential.

In the United States and Europe, there are numerous safety consulting firms of varying sizes; some may be small, yet highly specialized in specific domains. To ensure safety in the chemical industry, we too need a robust cadre of expert consultants to support enterprises. At present, professional consulting firms in China remain relatively few, and safety‑assessment agencies hold promise as key players in filling this gap—though their transition will by no means be easy.

How can safety assessment firms successfully transform? Many such firms are still exploring the issue and even grappling with it. Here are a few suggestions for your reference:

1. The safety management and technical expertise of corporate managers and engineers are steadily improving, which means the demand for generic, one-size-fits-all assistance is diminishing. What enterprises now require are in-depth, specialized services. We should focus on developing professional risk‑control solutions tailored to businesses; in this regard, many safety‑assessment firms still need to elevate their technical capabilities by learning from internationally advanced safety technologies and management practices. Chemical‑industry safety encompasses an extremely broad range of issues, and some organizations have tried to take on everything, pursuing whatever is most profitable—yet this approach may no longer be sustainable. As they undergo transformation, safety‑assessment firms can choose a specific niche and cultivate deep expertise in that area, enabling them to deliver greater value to clients while ensuring their own business growth proceeds naturally.

2. Providing concrete, actionable solutions. Many small and medium-sized chemical enterprises have relatively weak in-house safety expertise and insufficient engineering experience and capabilities; simply identifying problems is of limited value to them. The key lies in helping them address real‑world challenges, particularly by delivering tailored, context‑specific solutions. The industry urgently needs a robust cohort of safety consulting firms that can deliver such practical, end‑to‑end solutions. If safety assessment organizations can rise to this standard, their transformation will be essentially complete.

3. Government requirements for corporate compliance—ensuring adherence to legal and regulatory standards—are becoming increasingly stringent. Higher levels of compliance naturally reduce operational safety risks. Providing assistance and guidance to chemical enterprises in meeting applicable laws, regulations, and standards is highly valuable—and precisely where environmental assessment firms excel. Consider offering companies more comprehensive and specialized compliance support and services.

A major challenge hindering the transformation of safety‑assessment firms is the “ultra‑low‑price strategy” that has long characterized their operations. Many such agencies have become accustomed to competing on price, and this pricing approach has been one of the key factors contributing to the previously subpar quality of safety‑assessment services.

In the fields of safety management and safety‑related technical services, seemingly low prices often come at the expense of quality; for enterprises, what appears to be a bargain may in fact prove to be the most costly option. Winning contracts through rock‑bottom pricing inevitably leads to compromises in service—forcing firms to hire underqualified personnel with minimal experience—and while this may shave off some costs, it can result in far greater losses during the period of service. A single misguided recommendation can significantly inflate unnecessary expenditures, sow hidden risks, or even trigger major accidents. To ensure the healthy development of the entire industry, we must abandon the destructive practice of cutthroat price competition. Prolonged low‑price rivalry drives out high‑quality providers, prompting talented professionals to leave the field, leaving chemical companies struggling to find the expert services they truly need. We should oppose excessive profiteering, but reasonable profits are essential to sustaining the industry’s long‑term growth. We look forward to seeing many safety‑assessment firms undergo a transformative shift, becoming trusted partners that help chemical enterprises effectively mitigate operational risks.

Since the very first chemical plant was established, chemical safety has been a concern. However, many of us who study chemical engineering still lack sufficient knowledge of safety, a shortcoming that is closely linked to gaps in our university education.

In some foreign universities, chemical process safety has already become a dedicated academic discipline, whereas in China, very few institutions offer it as a mandatory course. It is essential that chemical process safety be made a compulsory subject for students majoring in chemical engineering, or at the very least that relevant key concepts be integrated into undergraduate and associate‑degree curricula to help students develop fundamental, sound understanding and principles.

A well-known British university (with a campus in China) annually invites industry experts to help review its chemical engineering curriculum, strategically integrating key process‑safety concepts and cutting‑edge practices into students’ learning pathways—from the first year through graduation. This approach enables students to understand how the industry approaches chemical safety at both the conceptual level and in terms of the core knowledge and methodologies required to ensure the safe operation of chemical plants, as well as the tools, software, and technical standards currently employed in the field. Over the past few years, I have been invited to participate in these review meetings and have also taken time to deliver specialized lectures on process safety to the university’s chemical engineering graduates. I am keenly hopeful that many domestic universities will adopt this model to cultivate their students.* [Note] Today’s students will become tomorrow’s engineers, managers, government officials, or business owners in our chemical industries; the foundational safety awareness they develop during their academic years will have a profoundly lasting impact.

Note: The author has consulted with Professor Zhao Jinsong, Head of the Department of Chemical Engineering at Tsinghua University. At present, the Department of Chemical Engineering at Tsinghua University employs a curriculum review process similar to the one described above, and some other universities may be adopting comparable practices as well.

Now, even domestic universities with chemical engineering programs are beginning to place greater emphasis on education related to chemical safety. However, many university instructors possess strong theoretical expertise but lack practical production experience, making it difficult to bridge the gap between theory and practice. How to effectively integrate industry best practices with university teaching is a question worth exploring. Recently, some universities have invited industry experts and academic faculty to co-author textbooks on safety, health, and the environment (EHS)—a highly commendable initiative!

Moreover, in recent years, safety engineering has become an extremely popular field of study. Given the unique nature of chemical‑process safety, if a safety engineering program is tailored to the chemical industry, it must not only equip students with sound safety principles, knowledge, and skills, but also ensure they acquire relevant process and engineering expertise—covering courses such as chemical engineering principles and physical chemistry.

I primarily work with enterprises, and my views on the aforementioned third-party organizations are based on distant observation, inevitably tinged with partiality and a limited perspective. However, one thing is beyond doubt: these third-party agencies are vital partners for chemical companies in achieving safety; when they perform well, they can help the chemical industry reduce catastrophic accidents. (To be continued)